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MODULE 1 BASIC LAWS OF CHEMISTRY, BASIC CLASSES OF
CHEMISTRY, BASIC CLASSES OF INORGANIC COMPOUNDS,
STRUCTURE OF MATTER. POWER ENGINEERING AND DIRECTION
OF CHEMICAL PROCESSES

CONTENTS MODULE 1 ATOMIC-MOLECULAR THEORY. LAWS OF

CHEMISTRY. PERIODIC LAW

LECTURE 1 BASIC CONCEPTS AND CHEMICAL PROVISIONS

PROGRAM QUESTIONS:

1.1 ATOM. MOLECULE. CHEMICAL ELEMENT

1.2 BASIC CHEMISTRY LAWS OF CONSERVATION OF MASS LAW

1.3 RELATIVE ATOMIC AND MOLECULAR MASSES. MOLE, MOLAR
MASS

1.1 Atom. Molecule. Chemical element

Substances consist of atoms or molecules that are in some way
interconnected. The masses of atoms and molecules are very small, so for

comparing their masses it is convenient to use relative atomic and molecular

masses, which indicate how many times the atom or molecule is lighter or heavier

than the standard value. At present, the atomic unit of mass is used as a standard.
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The atomic unit of mass (a.o.m.) is 1/12 of the mass of the Carbon C

isotope atom. The atomic mass unit is less than the usual standard mass (in grams)
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in 6.02 10 times. Therefore, the fair ratio:

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1 а.о.m. ∙ 6,02∙10 = 1 g

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